Electrical relay



H. W. BROWN.

ELECTRICAL RELAY. APPLICATION flLED m1. 7,1914.

1,341,629. P ed J 1111 1, 1920.

; wl/NgENTOR ATTORNEY I a side view, partially in section and par-UNITED STATES, PATENT OFFICE.

HAROLD W. BROWN, 0F ITHACA, NEW YORK, ASSIGNOR T0 WESTINGHOUSE ELECTRICAND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRICAL RELAY.

Specification of Letters Patent.

Patented June 1, 1920.

Application filed January 7, 1914; Serial No. 810,799.

1 injuries resulting from overloads and similar disturbances.

The object of my invention is to provide an electro-Inagnetic type ofrelay of the character indicated which shall have a time period betweenthe beginning of a flow of current that exceeds a predetermined amountand the instant when a circuit-breaker is tripped that is inverselyproportional to the amount by which the current exceeds thepredetermined amount.

It is broadly old in the prior art to provide a relay embodying aninverse time element feature but my present invention provides a relayconstituting an inverse time element feature of such novel constructionas to greatly increase its adjustments and to materially reduce the costof manufacturing the same.

My invention possesses exceedingly simple adjustments and has means forincreasing the time limit of its operation beyond that heretoforeprovided and it also possesses a greater flexibility of adjustmentthanhave previous relays of the above mentioned type.

In the accompanying drawing, Figure 1 is tially in elevation, of a-relayembodying my invention, and Fig. 2 is arear elevational view of therelay shown in Fig. 1.

Referring to the drawing, my'invention; comprises a stationary,magnetizable memher 1, a hollow movable magnetizable core member 2, anexciting winding 3 concentrically disposed with respect to the 'coremember 2, a spring 4for Opposingthe ac tion of the said movable coremember, a flexible member 5 to be associated withthe movable core.member 2 and the stationary member 1 to form a bellows 6,1 a movablecontact member 7 thatis suspended fromthelower portion 9 of the member 1and is normally 111 engagement wlth a-stati'onary contact member 8 thatis also suspended from the lower portion 9 of the member 1.

The movable core member'2 is slidably mounted in a non-magnetic tubularmember 10 which has an easily saturable magnetic vane or pole piece 11attached to its upper end for modifying the inverse action of the relay,according to its position. To the lower end of the member 2 is attacheda support 12 for the spring 4. In the lower portion of the member 2 isfitted a tubular 'member 13 having a helical groove on its outer surfaceextending through approximately one circumference to serve as a passagefor the escape of air. The lower part of the core 'member 2 is providedwith a relatively narrow longitudinal slot 20 of a length sli htly lessthan the length of the tube 13. indicator handle 14 for adjusting theposition of the same with respect to the slot 20 in the core member 2and for indicating on a scale (not shown), which is mounted onpredetermined overload.

The base member 9 has a downwardly pro ecting portion 15. that is screwthreaded to cooperate with a nut 16 having an annular groove to receivethe upper end of the spring 4 and being adjustable to set'the movable;core member 2 by any suitable- ,means. A suitable case 18 is provided toprotect the spring 4 and the contact members 7 and 8.

An insulating collar 19 is mounted ,upon

he tube13 is provided with an the support 12, the time of operation at athesupport' 1 2 for engaging the movable contact member 7 when the coremember 2 moves upwardly. The spring 4 is not Wound uniformly but thespacing of the turnsis so proportioned that, as the spring is compressedby turningcthe nut.1 6, a considerable number of "turns of the same'areclo s'edcons.ec-utively. Tl1I1 S,tlle gradient of the spring pressureissteeper 'whenthe relay is set'forheavier loads.

"When an overload or other disturbance occurs upon an electricalcircuit(not shown) an increased current that is proportional to the increasedcurrent flowing through the circuit will traverse the winding 3 of therelay and cause upward movement of the core member 2 against the actionof the spring l and the bellows 6 at a rate which is inverselyproportional to the excess'current traversing the electrical circuit.

By moving the indicator 14, the tube 13 is.

turned to change-the length of the path through the portion of thehelical groove through which the air passes, and thus change the time ofoperation at any value of current. The indicator is placed in a positioncorresponding to the time settlng de sired for certain values'ofcurrent; and for, any current exceeding that value, the relay willoperate, as hereinbefore described, in inverse ratio to the value of thecurrent.

The magnetic vane or pole piece 11 is unsaturated at relatively lowvalues of currents. Thus, the action of the relay will become relativelystronger at light loads and relatively weaker at heavy loads, and thus,the pull of the relay will be nearly the same at all loads. From theforegoing, it'will be understood that a substantially definite timeelement characteristic is obtained.

Although the specific .form of construction shown is that which ispreferred when my invention is used as a relay it is obvious 2: A relaycomprising a stationary mag ne izable member, a movable core member, awinding for the said members and an easily saturable' member disposedadjacent to the said winding on the movable core member for the purposeof obtaining a definite timeeleiment characteristic in the operation ofthe re ay.

3. In an electrical relay, the combination with a movable core member, astationary magnetizable member and a winding therefor, of a magnetizablevane dis osed on the said movable core member an adapted to becomesaturated under predetermined conditions to accentuate the time-elementcharacteristic of the relay.

.4. In a relay, the combination with a movable core member and a windingthere for, of an easily saturated vane mounted on the movable coremember, said vane being adapted to accentuate the definite time-limitcharacteristic of the relayr 5. In a relay, the combination with amovable core member and a winding therefor, of a magnetizable membermounted on the movable core member and adapted to become saturated whena predetermined current traverses the said winding.

6. A relay comprising a movable core member, a winding therefor and asaturable member, said saturable member being disposed adjacent the saidwinding on the said movable core member.

In testimony whereof I have hereunto subscribed my name this 29th day ofDecember, 1913.

HAROLD w. BROWN. Witnesses BERT T. BAKER, JAs. R. ROBINSON.

